Ryobi P135 18V One+ 6 Port Lithium Ion Battery Supercharger (18V Batteries Not Included / Charger Only)

Can you leave the batteries in the charger after charging with out hurting them

Electrician question:how many watts does it draw? i'm in an off grid rv with inverter, trying to decide if i need a 6 bank, or charge one at a time.

Wy is home depot selling this for $79?

Is this both 110v and 220v charger